Piston



uNrrEo'sTATes PATENT OFFICE.

CLAUDE E. COX, DETBOTT, MICHIGAN.

g PISTON.

Applioationflled April 21, 1921; Serial No. 463,348.

, l ribs 21 which need not be aswide as the Be itknown' that I, CLAUDE. E. Cox, a depth of flange 11 if said flan e is deep citizen. of the, UnitedStates, residin at enough for two ring grooves, as s own. At Detroit, in the-countyof Wayneand btate the center, the head 11, on its inner face, 5 of Michigan, have invented a new anduseis provided with a conical teat 22 to form :t'ul Piston,*of which the'following is a spec1- a basis for the working center 24. l fication. i In order to machine this piston so as to The object. of my invention is to provldo insure uniform thickness of the skirts and a light weight piston for internal .combusflange 11, and thus make minimum thickvtion engines, and an improved method of ness commercially possible, and also to com- 135 accurately-finishing the same in such manpensate distortions due to -release of interner as tomaintaingreat uniformity of crossnal stresses as external portions are removsection of its skirt. v v 1 it i t ed, I have devised the following method of The accompanyingdrawings illustrate my machining.

i To all who-m. itmay comem i 1 invention: Fig.1 1s a side elevation; Fig. 2 The rough castingsp of any-desired suitis a. section at right angles to the axisof able metal, is chucked uponan internal the pitman pin; Fig.3 is a .side elevation chuck 30 which engages close to the cyat right angles to the lane of Fig. 1; Fig. lindrica-l flange 11 and the. skirts l3, and at is anend elevation; ig. 5 is a transverse supporting the ends of said skirts. The

section through the pitinan pin; Fig. 6 is ends of the skirts 13, including ribl6, are

a diagram showing the manner of initial then carefully machined, preferably by at handling of the piston for the first maleast a final grinding, to form accurately chine operation; Fig. 7 is a diagram Sl10W- arc-shaped V ends 23, 23. The center 24 ing the manner of holding the piston for isalso formed while the piston is held upon boringthe pin bosses; and Fig. 8 is a dlathe internal chuck. gram showing the manner of holding the The piston is then clamped between a piston for, he external machining operacenter pin 25, which enters center 24, and tions. a head 26 provided with a circular V-shaped In the drawings 10 indicates h P1815011 groove 27 with which ends 23 of skirts 13 30 headprovided with a cyhndrical flange 11 will accurately fit. Thereupon bosses 17 are 0f l Sufilclent length to P611111t the bored and reamed by tools carried by arbors tion therein of adequate ring-grooves 12. 28

At diametrically opposlte .olnts the The piston is then mounted in a finishing flange 11 is ext nd d t0 form 5 Its machine provided with a head 26' similar ach havi g n g l extent f BP Q to head 26 and provided with a circular V- y At each g e501} skllt 1S stlfi shaped groove 27', being clamped thereon fined y f bf fi g flange by an internal clamping rod 29 carrying a gradually n r ng wlflith Q the P pin 30 fitting the bores of bosses 17. The

. of the skll't Junctlon Wlth flange piston is further supported by the usual but narrow Internally tail-stock pin 31 which enters center 24. each skirt 11 1s transversel stifi'ened by h usual t i and grinding operaseveral narrow lateral arcs aped ribs tions for forming and finishing grooves 12 .g fg i" by a nb and the external surfaces of head 10, flange lhe bo sses 1 7 17 iliii tlii: giimaii-pin are 11 i skirts 13 will performed while arranged between each pair of flanges 14 t plston 1s supportiidm the manner shpwn and approximately at the middle of the m Fig. 8. By follow1ng the above described length of the Piston and each boss is method the skirt walls and flange 11 may be ported by a of diverging thin arms 18, made much thnmer than has been hereto- 18 which merge into a flange 4 and flange fore considered practicable because no al- 1 at a 'unct'ion between h flanges 1 lowance has to be made for posslble eccenl d 4 h arm 1 i tifl d b an i tricity of inner and outer walls. The free n r rib 19, whi h xt nd f b 17 t ends of the skirts being firmly held by the flange 11, andan outer rib 20, which exseating of the Y-shaped ends 23 in the seat tends from boss 17 to the adjacent flange 14. 27 and27, 1t 1s apparent that the various 5 e inner face of head 11 is stifiened by' machining operations can be carried on l a v with great rapidity without liability of distortion. v

It will be noted that the triangles formed by head and the two pairs of arms 18 provide a rigid structure sion of the explosive forces'to the pitman, while the side thrust of the pitman upon the skirts 13 is somewhat flexibly resisted owing to the fact that arms 14'0f skirts 13 only at their junction with flan e 11; *Thisconstruction'aflords a desira- 1e flexibility in the skirts which insures against rupturing of-the oil film upon-which the'lskirts ride, :andjreduces piston-slap and resultarit noise. v r- I I claim as my invention: v 1. An integral pistoncomprising a head, ,a comparatively short cylindrical ring- -carrying.flange, circumferentially separated arc-shaped skirts, oross-pin'bosses, and two pairs of arms divergingat an angle less than 180degreesj connecting the cross pin bosses with. the skirts at points between the head and the axis of the bosses. I

" 2; An integral piston comprising ahead,

a comparatively short cylindricalringearrying flange, circumferentially separated arc-shaped skirts, transverse stiifening ribs on the "innerfaces-oi the skirts, cross-pin for the tr'ansmis- 18 join flanges carrying flange, circumferentially separated arc-shaped skirts, having inturned narrow flanges at their'edges, cross-pin bosses, and two pairs of angularly diverging arms connecting the cross-pin bosses Wltll the in turned flanges of the skirts at points be- .tweenthe headand the. axis of the bosses,

and transverse stiffening ribson the inner faces of the skirts. v v

4. Anintegral piston comprising ahead, a comparatively short cylindrical ringcarrying flange, circumferentially separated arc-shaped skirts, having inturned narrow flanges .at their edges, two pairs of angularly diverging arms connectingthe cross-pin bosses wlth the inturned flanges of the skirts at points 'between the head and the axis of the bosses. In witness whereof, I have-hereunto set my handat Chicago, 111., this 13tlrday of Aprn, A. D. one thousand nine hundredand CLAUDE cox.

twenty one.

cross-pin bosses, and 

